Hand cuffs pseudo lock device

[whippingboy]

I just thought i would share the details of my latest SB locking device.
I tried to create something that was (a) Easy to lock (b) Easy to unlock (c) had a fail safe built in.
What i came up with was the following.
Wooden post 100mm square with a 15mm hole drilled through it. My post was bolted vertically to the floor but it could be anywhere as long as it cannot be easily moved.
2 x m4 snap hooks , 2x 15mm copper pipe 40mm long , 1 x solder ring 15mm straight connector.
The m4 snap hooks push fit into the ends of the copper pipe. (slightly compress the pipe end to fix it there)
The two other ends of the copper pipe push fit into the straight connector . (put a tiny bend on the end so it is a very tight fit)
The whole assembly then passes through the wood so the opening ends of the snap hooks are just poking out of the post each side.
Then I can now go through a SB routine with the last item on my list to push my hand cuff loops onto the snap hooks.
You may be asking at this point - what is to stop me just pulling my arms apart and pulling both the pipes out of their connector?
Well one bit i missed out - the two pieces of copper pipe have a wire soldered to each of them. These two wires are carrying a current which is energizing a relay. The NC contacts of this relay are wired to a timer in series with a solenoid. The solenoid is hung from the ceiling and it carries a bag full of used oil.
Quite simply if the cuffs are pulled apart the solenoid will trigger and drop the oil ( safe but not desirable outcome )
So there is every incentive to wait until the timer finishes before trying to escape.
I have now used this successfully twice , and each time i was unable to find a way of cheating it.

[bobbi]

let me be the first to request a graphical diagram or photo or some sort of visual aid ^_^

[whippingboy]

Here's the basic device :

and this is a simple circuit for it:

though i went for a more elaborate control with a computer controller and some other sensors.
Hope this helps.

[bobbi]

that does make a lot more sense now, at least to me. that circuit gives me an idea for another idea i had too.